Ethyl 5-cyano-3-methoxy-2-(trifluoromethoxy)pyridine-4-carboxylate
Ethyl 5-cyano-4-methoxy-2-(trifluoromethoxy)pyridine-3-carboxylate
Ethyl 2-cyano-5-methoxy-4-(trifluoromethoxy)pyridine-3-carboxylate
Ethyl 2-cyano-3-methoxy-5-(trifluoromethoxy)pyridine-4-carboxylate